Shedding light on solar technologies—A techno-economic assessment and its policy implications

Solar power technologies will have to become a major pillar in the world's future energy system to combat climate change and resource depletion. However, it is unclear which solar technology is and will prove most viable. Therefore, a comprehensive comparative assessment of solar technologies along the key quantitative and qualitative competitiveness criteria is needed. Based on a literature review and detailed techno-economic modeling for 2010 and 2020 in five locations, we provide such an assessment for the three currently leading large-scale solar technologies. We show that today these technologies cannot yet compete with conventional forms of power generation but approach competitiveness around 2020 in favorable locations. Furthermore, from a global perspective we find that none of the solar technologies emerges as a clear winner and that cost of storing energy differs by technology and can change the order of competitiveness in some instances. Importantly, the competitiveness of the different technologies varies considerably across locations due to differences in, e.g., solar resource and discount rates. Based on this analysis, we discuss policy implications with regard to fostering the diffusion of solar technologies while increasing the efficiency of policy support through an adequate geographical allocation of solar technologies.     

AN EXAMINATION OF ASTM PROCEDURES FOR DETERMINING SULFUR FORMS IN COAL

Several raw coals of various ranks were used to examine the effects of some of the variations in ASTM procedures on analytical results obtained for total sulfur and sulfur forms. ASTM procedures were also used to determine pyritic sulfur in two coals cleaned by selective agglomeration processes.In addition, organic sulfur values obtained by the indirect ASTM procedure were compared to those obtained directly by leaching coal with hot HNO3 followed by total sulfur determinations on the coal residue.

Differences in the ASTM leaching procedure with HNO3 did not significantly affect the pyritic sulfur results for any of the coals. However, small differences between the referee (leaching coal with HNO3) versus alternate (leaching coal ash with HCl) ASTM procedures for determining pyritic sulfur were observed.Neithei: procedure was consistently higher than the other.     

展望22nm技术节点

为了实现22nm技术节点,工程师必须在许多方面做出重大决定,例如：是否要从平面化的CMOS器件结构转变为多栅结构;是否要使用不同的沟道材料;以及是否要用铜插入来代替钨插入。     

Modeling Groups of Plausible Virtual Pedestrians

In a proposed methodology for modeling dynamic crowd scenarios, a video corpus informs the modeling process, after which the resultant animations undergo perception-based evaluation. The aim is to improve the crowd's visual plausibility rather than the simulation's correctness. A real-life crowd animation system demonstrates the methodology's practical application.     

Properties of cutoff corrugated surfaces for corrugated horn design

Corrugated horns involve a junction between the corrugated surface and a conducting groundplane. Proper horn design requires an understanding of the electromagnetic properties of the corrugated surface and this junction. An integral equation solution has been used to study the influence of corrugation density and tooth thickness on the power loss, surface current, and the scattering from a groundplane-corrugated surface junction.     

Interaction between carbon dioxide and ionic liquids: Novel electrolyte candidates for safer Li-ion batteries

Ionic liquids (ILs) are typically molten salts at temperatures lower than 100 °C. Because of their thermal and electrochemical properties, they are good candidates to replace the state-of-the-art electrolytes used in today's Li-ion batteries. These commercial batteries often suffer from hazards caused by possible misuse. Elevated voltages and high temperatures usually lead to electrolyte degradation due to parasitic reactions with the electrodes leading to gas (mainly CO₂) evolution and may then eventually catch fire. Also, ILs are able to dissolve various gas molecules, making it possible to prevent a built-up of an overpressure inside the battery in case of undesired gas evolution. In this work, CO₂ storage in two different ionic liquids, i.e. PYR₁₄TFSI and [BMIm][BF4] is studied with regard to their respective Li-salt. Mixtures of ILs plus different concentrations of CO₂ were made. Phase diagrams of the pressure vs. temperature of the systems “liquid + vapour” to liquid transitions are drawn. Data points from 1.5 bar to 70 bar are collected with a Cailletet apparatus. Both of the ILs show good CO₂ dissolution ability; an increase of the temperature leads to an increase of the pressure needed to dissolve similar amounts of CO₂. The presence of a Li-salt hampers gas storage, particularly for PYR₁₄TFSI. A model based on the Langmuir adsorption theory is used to describe the solubility of the CO₂ in [BMIm][BF4]. The PYR₁₄TFSI IL does not obey the Langmuir-like solubility behaviour. Hence, the solubility then is described by the formation of discrete bonds between the CO₂ and the solvent, similarly to the concept of adspecies and surface sites.     

PHASE-SPACE DIFFUSION EQUATIONS FOR SINGLE BROWNIAN PARTICLE MOTION NEAR SURFACES

In numerous physical processes involving the motion of micron and submicron sized particles near surfaces, such as the filtration of hydrosols and aerosols, the particle motion is the net result of the combined effects of fluid convection, external forces, particle inertia, Brownian particle motion, and particle-surface fluid dynamic interactions. The most general method of describing particle motion under the combined action of these effects is through the so-called Fokker-Planck equation. In the absence of particle-surface fluid dynamic interactions, the Fokker-Planck equation is well-known, and it has been applied in a general way to problems involving the adsorption or deposition of Brownian particles onto surfaces through a solution technique known as the Brownian dynamics simulation method.

In this study, the Fokker-Planck equation for Brownian particle motion near surfaces is generalized to include particle-surface fluid dynamic interactions. The Fokker-Planck equation is shown to follow from the Liouville equation for the Brownian particle and n-fluid molecules present in the system, thus, establishing a firm theoretical foundation for the Fokker-Planck equation and the various other phase-space diffusion equations that follow from it.

Based on diagonalization of the Fokker-Planck equation, its short-time behavior is also derived here which enables a generalization of the Brownian dynamics method for the study of particle motion near surfaces including fluid dynamic interactions. Additionally, a perturbation solution of the Fokker-Planck equation under the conditions of small, but finite particle Stokes number is also derived. These solutions are shown to agree with previously given representations of the Smoluchowski or convective-diffusion equation for Brownian particle motion near surfaces, as well as with inertial corrections to the Smoluchowski equation available in the literature. This latter equation is also generalized here to include particle-surface fluid dynamic interactions.     

Fatty acid metabolism in hypoxic rat liver

Fatty acid metabolism was investigated in adult male albino rats exposed to hypobaric hypoxia at 25,000 ft simulated altitude for 6 h at 32 degrees C. Oxidation and esterification of palmitic acid-1-14C and de novo lipogenesis from acetate-1-14C were studied. Palmitic acid-1-14C oxidation in liver slices was normal while acetoacetate formation was increased. In vivo esterification of palmitic acid-1-14C to form triglycerides was increased while formation of phosphatidylcholine and phosphatidylethanolamine was observed to decrease. Decreased incorporation into plasma phosphatidylcholine with unaltered total activity in plasma triglycerides was observed. The incorporation of acetate-1-14C was observed to remain unaltered in triglycerides and phospholipids of liver with a similar pattern in the plasma indicating unaltered de novo lipogenesis. There appears to be increased esterification of fatty acids with probably impaired release of triglycerides into plasma while fatty acid biosynthesis remains unaffected.     

Differential responses to male and female depressive reactions.

Suggests that the commonly reported preponderance of female over male depression in incidence and prevalence studies requires further analysis. One explanation is that the social consequences of expression of depressive symptomatology are different for males and females. A comparison of 157 male and 189 female undergraduates' reactions to male and female case histories of common reactions to stress confirmed the hypothesis. Depression elicited more rejection of males than of females, and the sex difference in rejection of depression was more pronounced than for anxiety or flat affect-detached responses. A discriminant analysis suggested that depressed males are especially likely to be perceived as impaired in role functioning as compared with depressed females. Results suggest that depressed males are not rejected for expression of emotionality as such. Speculations about the causes and consequences of differential rejection of depression are noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)